Determination of the local configuration of interacting defects in a crystalline, periodic solid is problematic because defects typically do not have a long-range periodicity. Uranium dioxide, the primary fuel for fission reactors, exists in hyperstoichiometric form, UO(2+x). Those excess oxygen atoms occur as interstitial defects, and these defects are not random but rather partially ordered. ...

In an earlier paper, we observed that PastSet (our experimental tuple space system) was 1.83 times faster on global reductions than LAM-MPI. Our hypothesis was that this was due to the better resource usage of the PATHS framework (an extension to PastSet that supports orchestration and configuration) due to a mapping of the communication and operations which matched the computing resources and ...

A heterogeneous cluster can incur the performance degradation caused by the load unbalance in executing the application for homogeneous cluster. Also, the total execution time can be improved by neglecting some of the PEs because communication time is reduced. This study examines to invoke multiple processes on fast processing elements (PEs) to avoid load unbalance. In this study, the execution...

This paper tries to tackle the problem of providing retrofitting network QoS in clustered configurations. For this purpose, we designed a QoS manager which runs on each of the internal cluster nodes and controls network I/O of local interface cooperating with peer managers on other nodes towards a certain QoS policy. First, we show the design of control framework, contending that an end-host ma...

Clusters have made the jump from lab prototypes to fullfledged production computing platforms. The number, variety, and specialized configurations of these machines are increasing dramatically with 32 – 128 node clusters being commonplace in science labs. The evolving nature of the platform is to target generic PC hardware to specialized functions such as login, compute, web server, file server...

Pauli-projected random gaussians are used as a representation to solve the shell model equations. The elements of the representation are chosen by a variational procedure. This scheme is particularly suited to describe cluster formation and cluster decay in nuclei. It overcomes the basis-size problem of the ordinary shell model and the technical difficulties of the cluster-configuration shell m...

Linear Programming (LP) relaxations have become powerful tools for finding the most probable (MAP) configuration in graphical models. These relaxations can be solved efficiently using message-passing algorithms such as belief propagation and, when the relaxation is tight, provably find the MAP configuration. The standard LP relaxation is not tight enough in many real-world problems, however, an...

Today, Beowulf systems are managed by operating on each node as a stand alone machine rather than a parallel system. In the present work, Yabat, a new software tool deviced to configure and monitor a Linux cluster, is described. To achieve a single system view, Yabat allows network services configuration on both server and client side, centralized configuration of nodes network parameters and g...

In this paper, we present a cluster computing environment established at a minority serving institution that aims to provide services for research and education in an undergraduate student body. We will address the cost efficiency of the cluster computing environment; student participation in the configuration of the lab; and research activities performed on the cluster that involves faculty/st...

Opus is an Opteron based cluster system with InfiniBand interconnect. Grid middleware provide the integration into CampusGrid and D-Grid projects. Mentionable details of hardware and software equipment as well as configuration of the cluster will be introduced. Performance measurements show that InfiniBand is not only well suited for message-passing based parallel applications but also competit...